#include<stdio.h>
int main()
{
	int a = 0, b = 0, c = 0;
	while(scanf("%d %d %d",&a,&b,&c)!=EOF)
		while (a > 0 && b > 0 && c > 0 && a < 1000 && b < 1000 && c < 1000)
		{
			if (a + b > c && a +c>b&&b+c>a)
			{
				if (a == b && a == c)
					printf("Equilateral triangle!\n");
				else if (a == b || a == c || b == c)
					printf("Isosceles triangle!\n");
				else
					printf("Ordinary triangle!\n");
			}
			else
				printf("Not a triangle!\n");
			break;
		}
	  
	return 0;
}

